Forbes.com: A Hacker's Guide To RFID - http://www.forbes.com/business/commerce/2004/07/29/cx_ah_0729rfid.html Article on RFID tag security, with links to related articles.
The Nation: The Trouble with RFID - http://www.thenation.com/doc.mhtml?i=20040216&s=garfinkel Long article about privacy concerns related to the technology.
Ross Mayfield's Weblog: RFID Hacks - http://ross.typepad.com/blog/2003/08/rfid_hacks.html Weblog entry argues that the more people grapple with RFID to learn how it operates and how it can be manipulated, worries about its misuse should decrease.
The Guardian: Tesco tests spy chip technology - http://www.guardian.co.uk/uk_news/story/0%2C3604%2C1001211%2C00.html Article in which Tesco gets accused of tagging packs of razor blades to track buyers.
csmonitor.com - Can your razor blade spy on you? - http://www.csmonitor.com/2003/1106/p14s01-stct.html Radio frequency identification tags could simplify inventory, but they worry privacy advocates.